Exit Rumsfeld.(Donald H. Rumsfeld and his merits )

DONALD RUMSFELD's departure as secretary of defense was a necessary precondition for President Bush to win any measure of public support for the changes his Iraq policy needs. It was also justified on the merits. More than three years on, the Iraq War is arguably going more poorly than ever.

Rumsfeld had lost the ability to speak with much credibility about the war. He has become a radioactive figure partly because of vicious and unfair attacks on him from the left and (occasionally) the right, attacks against which we have often defended him. But he is also radioactive because he is associated with the biggest failure of the Bush administration, one that sank the Republican party on Election Day and that, much more important, threatens a dangerous and long-lasting setback to the interests of the United States.

Rumsfeld is a talented and principled public servant whose legacy will include many accomplishments. His invasion plan for Afghanistan was revolutionary, coupling small American teams on the ground with precision airpower. His Iraq invasion plan emphasized joint operations by the military's different branches, and substituted speed for mass in a lightning strike that toppled Saddam in weeks and defied all the skeptics.

Against opposition from the Pentagon bureaucracy, Rumsfeld has pushed to transform the military. The Army is moving from an emphasis on heavy divisions designed to fight the Soviets to a more supple system of smaller, rotating combat brigades. Rumsfeld has killed ill-considered weapon systems such as the Crusader, a laughably immobile piece of notionally mobile artillery. He has modernized the Pentagon's personnel system and reorganized its intelligence operations to make them more effective.

He has always been visionary on missile defense, realizing that the ABM treaty was a relic and that the U.S. had to respond to the new strategic environment created by the threat of rogue-state ballistic missiles.

Finally, he believed that civilians should run the Pentagon, and held to that belief despite the bizarre ad hoc alliance of disgruntled generals and media who thought the brass should be calling the shots. That was how the Pentagon had operated in the Clinton years, when it had basically slipped (inept) civilian control.

These achievements speak to Rumsfeld's strengths as a public servant. But over time, as conditions in Iraq have drifted downward, his ...